If there's a reason that everyone should read this book, it's more so that they are aware of these tactics.
I assure you that doing so is both extremely difficult (because we're selfishly interested in ourselves most of the time) and kind (because the other person rarely receives such selfless attention.)
It's only cringe inducing if someone is using these tactics without actually being interested in others. Carnegie definitely does not advocate for being such a person.
I really need to re-read it, but my basic takeaway was "Don't be a dick" - and maybe my suspicion is right that it (although it is very old) still play on subtle differences of American and European (to be more specific: German) work culture. I'd absolutely say we're not as nice and polite, but more direct - also more honest. But that could also be my limited experience in a non-significant amount of companies and fields. :P
You have to work to cultivate those actions to be genuine. I've been following the Buddhism path, and it's helped me become more genuine.
Source: Read that book this year. Thought about the same thing.